27. B
28. 800 more people
29. He should receive $11.20 back. I came up with this by taking 81 (the total cost of the items) and subtracting 15%. After that, I got 68.85-the price after using the coupon. Then, I added the total amount of money he had and came up with 80 (he had 4 twenty dollar bills). Finally, I took away 68.85 from 80 and ended with the answer 11.20.
30. Store b is offering a better deal for the shoes. After using the percent discount for store a, I came up with 59.50. However, when I did the same with store b, I ended with 51.30, the better deal of the two stores.
